1/*
2 *  linux/fs/hpfs/ea.c
3 *
4 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5 *
6 *  handling extended attributes
7 */
8
9#include "hpfs_fn.h"
10
11/* Remove external extended attributes. ano specifies whether a is a
12   direct sector where eas starts or an anode */
13
14void hpfs_ea_ext_remove(struct super_block *s, secno a, int ano, unsigned len)
15{
16	unsigned pos = 0;
17	while (pos < len) {
18		char ex[4 + 255 + 1 + 8];
19		struct extended_attribute *ea = (struct extended_attribute *)ex;
20		if (pos + 4 > len) {
21			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
22				ano ? "anode" : "sectors", a, len);
23			return;
24		}
25		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
26		if (ea_indirect(ea)) {
27			if (ea_valuelen(ea) != 8) {
28				hpfs_error(s, "ea_indirect(ea) set while ea->valuelen!=8, %s %08x, pos %08x",
29					ano ? "anode" : "sectors", a, pos);
30				return;
31			}
32			if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 9, ex+4))
33				return;
34			hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
35		}
36		pos += ea->namelen + ea_valuelen(ea) + 5;
37	}
38	if (!ano) hpfs_free_sectors(s, a, (len+511) >> 9);
39	else {
40		struct buffer_head *bh;
41		struct anode *anode;
42		if ((anode = hpfs_map_anode(s, a, &bh))) {
43			hpfs_remove_btree(s, &anode->btree);
44			brelse(bh);
45			hpfs_free_sectors(s, a, 1);
46		}
47	}
48}
49
50static char *get_indirect_ea(struct super_block *s, int ano, secno a, int size)
51{
52	char *ret;
53	if (!(ret = kmalloc(size + 1, GFP_NOFS))) {
54		pr_err("out of memory for EA\n");
55		return NULL;
56	}
57	if (hpfs_ea_read(s, a, ano, 0, size, ret)) {
58		kfree(ret);
59		return NULL;
60	}
61	ret[size] = 0;
62	return ret;
63}
64
65static void set_indirect_ea(struct super_block *s, int ano, secno a,
66			    const char *data, int size)
67{
68	hpfs_ea_write(s, a, ano, 0, size, data);
69}
70
71/* Read an extended attribute named 'key' into the provided buffer */
72
73int hpfs_read_ea(struct super_block *s, struct fnode *fnode, char *key,
74		char *buf, int size)
75{
76	unsigned pos;
77	int ano, len;
78	secno a;
79	char ex[4 + 255 + 1 + 8];
80	struct extended_attribute *ea;
81	struct extended_attribute *ea_end = fnode_end_ea(fnode);
82	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
83		if (!strcmp(ea->name, key)) {
84			if (ea_indirect(ea))
85				goto indirect;
86			if (ea_valuelen(ea) >= size)
87				return -EINVAL;
88			memcpy(buf, ea_data(ea), ea_valuelen(ea));
89			buf[ea_valuelen(ea)] = 0;
90			return 0;
91		}
92	a = le32_to_cpu(fnode->ea_secno);
93	len = le32_to_cpu(fnode->ea_size_l);
94	ano = fnode_in_anode(fnode);
95	pos = 0;
96	while (pos < len) {
97		ea = (struct extended_attribute *)ex;
98		if (pos + 4 > len) {
99			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
100				ano ? "anode" : "sectors", a, len);
101			return -EIO;
102		}
103		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return -EIO;
104		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
105			return -EIO;
106		if (!strcmp(ea->name, key)) {
107			if (ea_indirect(ea))
108				goto indirect;
109			if (ea_valuelen(ea) >= size)
110				return -EINVAL;
111			if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), buf))
112				return -EIO;
113			buf[ea_valuelen(ea)] = 0;
114			return 0;
115		}
116		pos += ea->namelen + ea_valuelen(ea) + 5;
117	}
118	return -ENOENT;
119indirect:
120	if (ea_len(ea) >= size)
121		return -EINVAL;
122	if (hpfs_ea_read(s, ea_sec(ea), ea_in_anode(ea), 0, ea_len(ea), buf))
123		return -EIO;
124	buf[ea_len(ea)] = 0;
125	return 0;
126}
127
128/* Read an extended attribute named 'key' */
129char *hpfs_get_ea(struct super_block *s, struct fnode *fnode, char *key, int *size)
130{
131	char *ret;
132	unsigned pos;
133	int ano, len;
134	secno a;
135	struct extended_attribute *ea;
136	struct extended_attribute *ea_end = fnode_end_ea(fnode);
137	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
138		if (!strcmp(ea->name, key)) {
139			if (ea_indirect(ea))
140				return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
141			if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
142				pr_err("out of memory for EA\n");
143				return NULL;
144			}
145			memcpy(ret, ea_data(ea), ea_valuelen(ea));
146			ret[ea_valuelen(ea)] = 0;
147			return ret;
148		}
149	a = le32_to_cpu(fnode->ea_secno);
150	len = le32_to_cpu(fnode->ea_size_l);
151	ano = fnode_in_anode(fnode);
152	pos = 0;
153	while (pos < len) {
154		char ex[4 + 255 + 1 + 8];
155		ea = (struct extended_attribute *)ex;
156		if (pos + 4 > len) {
157			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
158				ano ? "anode" : "sectors", a, len);
159			return NULL;
160		}
161		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return NULL;
162		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
163			return NULL;
164		if (!strcmp(ea->name, key)) {
165			if (ea_indirect(ea))
166				return get_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), *size = ea_len(ea));
167			if (!(ret = kmalloc((*size = ea_valuelen(ea)) + 1, GFP_NOFS))) {
168				pr_err("out of memory for EA\n");
169				return NULL;
170			}
171			if (hpfs_ea_read(s, a, ano, pos + 4 + ea->namelen + 1, ea_valuelen(ea), ret)) {
172				kfree(ret);
173				return NULL;
174			}
175			ret[ea_valuelen(ea)] = 0;
176			return ret;
177		}
178		pos += ea->namelen + ea_valuelen(ea) + 5;
179	}
180	return NULL;
181}
182
183/*
184 * Update or create extended attribute 'key' with value 'data'. Note that
185 * when this ea exists, it MUST have the same size as size of data.
186 * This driver can't change sizes of eas ('cause I just don't need it).
187 */
188
189void hpfs_set_ea(struct inode *inode, struct fnode *fnode, const char *key,
190		 const char *data, int size)
191{
192	fnode_secno fno = inode->i_ino;
193	struct super_block *s = inode->i_sb;
194	unsigned pos;
195	int ano, len;
196	secno a;
197	unsigned char h[4];
198	struct extended_attribute *ea;
199	struct extended_attribute *ea_end = fnode_end_ea(fnode);
200	for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea))
201		if (!strcmp(ea->name, key)) {
202			if (ea_indirect(ea)) {
203				if (ea_len(ea) == size)
204					set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
205			} else if (ea_valuelen(ea) == size) {
206				memcpy(ea_data(ea), data, size);
207			}
208			return;
209		}
210	a = le32_to_cpu(fnode->ea_secno);
211	len = le32_to_cpu(fnode->ea_size_l);
212	ano = fnode_in_anode(fnode);
213	pos = 0;
214	while (pos < len) {
215		char ex[4 + 255 + 1 + 8];
216		ea = (struct extended_attribute *)ex;
217		if (pos + 4 > len) {
218			hpfs_error(s, "EAs don't end correctly, %s %08x, len %08x",
219				ano ? "anode" : "sectors", a, len);
220			return;
221		}
222		if (hpfs_ea_read(s, a, ano, pos, 4, ex)) return;
223		if (hpfs_ea_read(s, a, ano, pos + 4, ea->namelen + 1 + (ea_indirect(ea) ? 8 : 0), ex + 4))
224			return;
225		if (!strcmp(ea->name, key)) {
226			if (ea_indirect(ea)) {
227				if (ea_len(ea) == size)
228					set_indirect_ea(s, ea_in_anode(ea), ea_sec(ea), data, size);
229			}
230			else {
231				if (ea_valuelen(ea) == size)
232					hpfs_ea_write(s, a, ano, pos + 4 + ea->namelen + 1, size, data);
233			}
234			return;
235		}
236		pos += ea->namelen + ea_valuelen(ea) + 5;
237	}
238	if (!le16_to_cpu(fnode->ea_offs)) {
239		/*if (le16_to_cpu(fnode->ea_size_s)) {
240			hpfs_error(s, "fnode %08x: ea_size_s == %03x, ea_offs == 0",
241				inode->i_ino, le16_to_cpu(fnode->ea_size_s));
242			return;
243		}*/
244		fnode->ea_offs = cpu_to_le16(0xc4);
245	}
246	if (le16_to_cpu(fnode->ea_offs) < 0xc4 || le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200) {
247		hpfs_error(s, "fnode %08lx: ea_offs == %03x, ea_size_s == %03x",
248			(unsigned long)inode->i_ino,
249			le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
250		return;
251	}
252	if ((le16_to_cpu(fnode->ea_size_s) || !le32_to_cpu(fnode->ea_size_l)) &&
253	     le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5 <= 0x200) {
254		ea = fnode_end_ea(fnode);
255		*(char *)ea = 0;
256		ea->namelen = strlen(key);
257		ea->valuelen_lo = size;
258		ea->valuelen_hi = size >> 8;
259		strcpy(ea->name, key);
260		memcpy(ea_data(ea), data, size);
261		fnode->ea_size_s = cpu_to_le16(le16_to_cpu(fnode->ea_size_s) + strlen(key) + size + 5);
262		goto ret;
263	}
264	/* Most the code here is 99.9993422% unused. I hope there are no bugs.
265	   But what .. HPFS.IFS has also bugs in ea management. */
266	if (le16_to_cpu(fnode->ea_size_s) && !le32_to_cpu(fnode->ea_size_l)) {
267		secno n;
268		struct buffer_head *bh;
269		char *data;
270		if (!(n = hpfs_alloc_sector(s, fno, 1, 0))) return;
271		if (!(data = hpfs_get_sector(s, n, &bh))) {
272			hpfs_free_sectors(s, n, 1);
273			return;
274		}
275		memcpy(data, fnode_ea(fnode), le16_to_cpu(fnode->ea_size_s));
276		fnode->ea_size_l = cpu_to_le32(le16_to_cpu(fnode->ea_size_s));
277		fnode->ea_size_s = cpu_to_le16(0);
278		fnode->ea_secno = cpu_to_le32(n);
279		fnode->flags &= ~FNODE_anode;
280		mark_buffer_dirty(bh);
281		brelse(bh);
282	}
283	pos = le32_to_cpu(fnode->ea_size_l) + 5 + strlen(key) + size;
284	len = (le32_to_cpu(fnode->ea_size_l) + 511) >> 9;
285	if (pos >= 30000) goto bail;
286	while (((pos + 511) >> 9) > len) {
287		if (!len) {
288			secno q = hpfs_alloc_sector(s, fno, 1, 0);
289			if (!q) goto bail;
290			fnode->ea_secno = cpu_to_le32(q);
291			fnode->flags &= ~FNODE_anode;
292			len++;
293		} else if (!fnode_in_anode(fnode)) {
294			if (hpfs_alloc_if_possible(s, le32_to_cpu(fnode->ea_secno) + len)) {
295				len++;
296			} else {
297				/* Aargh... don't know how to create ea anodes :-( */
298				/*struct buffer_head *bh;
299				struct anode *anode;
300				anode_secno a_s;
301				if (!(anode = hpfs_alloc_anode(s, fno, &a_s, &bh)))
302					goto bail;
303				anode->up = cpu_to_le32(fno);
304				anode->btree.fnode_parent = 1;
305				anode->btree.n_free_nodes--;
306				anode->btree.n_used_nodes++;
307				anode->btree.first_free = cpu_to_le16(le16_to_cpu(anode->btree.first_free) + 12);
308				anode->u.external[0].disk_secno = cpu_to_le32(le32_to_cpu(fnode->ea_secno));
309				anode->u.external[0].file_secno = cpu_to_le32(0);
310				anode->u.external[0].length = cpu_to_le32(len);
311				mark_buffer_dirty(bh);
312				brelse(bh);
313				fnode->flags |= FNODE_anode;
314				fnode->ea_secno = cpu_to_le32(a_s);*/
315				secno new_sec;
316				int i;
317				if (!(new_sec = hpfs_alloc_sector(s, fno, 1, 1 - ((pos + 511) >> 9))))
318					goto bail;
319				for (i = 0; i < len; i++) {
320					struct buffer_head *bh1, *bh2;
321					void *b1, *b2;
322					if (!(b1 = hpfs_map_sector(s, le32_to_cpu(fnode->ea_secno) + i, &bh1, len - i - 1))) {
323						hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
324						goto bail;
325					}
326					if (!(b2 = hpfs_get_sector(s, new_sec + i, &bh2))) {
327						brelse(bh1);
328						hpfs_free_sectors(s, new_sec, (pos + 511) >> 9);
329						goto bail;
330					}
331					memcpy(b2, b1, 512);
332					brelse(bh1);
333					mark_buffer_dirty(bh2);
334					brelse(bh2);
335				}
336				hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno), len);
337				fnode->ea_secno = cpu_to_le32(new_sec);
338				len = (pos + 511) >> 9;
339			}
340		}
341		if (fnode_in_anode(fnode)) {
342			if (hpfs_add_sector_to_btree(s, le32_to_cpu(fnode->ea_secno),
343						     0, len) != -1) {
344				len++;
345			} else {
346				goto bail;
347			}
348		}
349	}
350	h[0] = 0;
351	h[1] = strlen(key);
352	h[2] = size & 0xff;
353	h[3] = size >> 8;
354	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l), 4, h)) goto bail;
355	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 4, h[1] + 1, key)) goto bail;
356	if (hpfs_ea_write(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l) + 5 + h[1], size, data)) goto bail;
357	fnode->ea_size_l = cpu_to_le32(pos);
358	ret:
359	hpfs_i(inode)->i_ea_size += 5 + strlen(key) + size;
360	return;
361	bail:
362	if (le32_to_cpu(fnode->ea_secno))
363		if (fnode_in_anode(fnode)) hpfs_truncate_btree(s, le32_to_cpu(fnode->ea_secno), 1, (le32_to_cpu(fnode->ea_size_l) + 511) >> 9);
364		else hpfs_free_sectors(s, le32_to_cpu(fnode->ea_secno) + ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9), len - ((le32_to_cpu(fnode->ea_size_l) + 511) >> 9));
365	else fnode->ea_secno = fnode->ea_size_l = cpu_to_le32(0);
366}
367
368